The Influence Of Varying SOAs Of Endogenous And Exogenous Attention On The SNARC Effect

The investigation of SNARC effect on the mechanism of number processing is one of the hot topics of psychology. Currently, the research of number processing has been changed from separately on number to connect number with other cognitive process, which could help to explore the influence of other cognitive process on number processing and know more about mechanism of number processing. The visual selective attention can be classified as endogenous attention and exogenous attention. Endogenous attention is arosed by behavior goals, whereas exogenous attention is summoned by exterior stimulate in the environment..This research use ERP(event-related potentials) to explore influence of visual selective attention on the SNARC effect.In this experiment, all subjects take the same task. Subjects’ task was to decide whether the presented number was odd or even. In experiment one, the selective attention was caused by central cues, which contain valid cues and invalid cues. In experiment two, all were same as experiment one, except for the way which cause selective attention. In this experiment, selective attention was caused by peripheral cues, which also contain valid cues and invalid cues.The results showed that(1) Under the attended condition of endogenous cue, on the behavior level, the reaction time difference between valid cue and invalid cue was gradually increased with the increasing SOAs; On the ERPs level, When SOA was 500 ms and 700 ms, there are significant differences in the N1 and P3 amplitudes for the valid cue and the invalid cue.(2) Under the attended condition of endogenous cue, on the behavior level, SNARC effect are significant on all SOA level; On the ERPs level, the N1 and P3 amplitude showed a modulation in the effect of congruency in the valid cue condition on all SOA level.(3) Under the attended condition of exogenous cue, on the behavior level, When SOA was 300 ms and 500 ms, the reaction time difference between valid cue and invalid cue was bigger; On the ERPs level, When SOA was 300 ms and 500 ms, there are significant differences in the N1 and P3 amplitudes for the valid cue and the invalid cue.(4) Under the attended condition of exogenous cue, on the behavior level, SNARC effect are significant on all SOA level; On the ERPs level, on all SOA level, only the N1 amplitude showed a modulation in the effect of congruency in the valid cue condition, however, there was no significant interaction of cue validity and congruency in P3 amplitude.